Maybe not all the time, but in Malkin's first 100 point season (2007-08), over 53 games, Crosby played 432 ES minutes without Malkin and 360 with him. And even when they were apart, teams were forced to decide whether their top defensive pairing is out there against Crosby's line, or against Malkin's line.
The Avs 2C in Mack's first 107 point pace season (2017-18) was Carl Soderberg, so there's no question who was getting the other team's focus. Their PP1 that year was Mack's line + Tyson Barrie + one of Kerfoot/Jost/Andrighetto, so Mack was very clearly the focus there too.
(Since you wanted to make the comparison, over 80 game together last year, Drai played 818 5v5 minutes without McDavid, and 550 with him. If you do the math, that's Crosby playing 45.45% of his ES minutes with Malkin, and Drai playing ~40.2% of his ES minutes with McDavid, meaning Crosby/Malkin actually played together more frequently when healthy than McDavid/Drai)